1. Field of the Invention
The present invention relates to an armored rubber composition for use as an inner tube for a cycle or a raft.
2. Description of the Related Art
The bicycle commuter and/or bike enthusiast frequently encounters flat tires due to blunt forces, thorns, glass, wood chips, metal objects and other debris. A flat tire can be a significant hassle. In order to anticipate and respond to flat bicycle tires, the biker must carry a number of items, including patches, glue, tools, and a pump. However, patching a tire can be cumbersome and very greasy for the hands. Even after the cyclist fixes the flat, he or she will often discover that the next day, the tire is flat again due to stresses placed upon, and pinching of, the inner tube during the process of fixing the flat.
Some cyclists will use a gooey, fibrous, liquid sealant, sometimes called xe2x80x9cslime.xe2x80x9d Liquid sealants clog the punctures temporarily, and there are a number of draw backs to using them. In general, liquid sealants are affected by gravity, and they settle to the bottom of the tire. They also can fail outside of the optimum suggested temperature. Certain, if not all liquid sealants, for example, disrupt the balance of the tire, cause noise and eventually damage the rim. Occasionally, the liquid sealant will leak out of the tube and valve.
One product, known as a xe2x80x9ctoughy,xe2x80x9d comprising a plastic strip, is placed between the tube and the tire to aid the tire in resisting punctures. Toughies do not always work because they do not protect the entire tube, only the top surface, and they do not prevent xe2x80x9csnake bitesxe2x80x9dxe2x80x94that is, when the tube is pinched between the rim and tire, or between the rim and a tire tool used to remove the tire. Moreover, toughies have been known to abrade the outside surface of the tube, and actually create conditions leading to tube failure. A number of patents have attempted to address the issue of puncture prevention and/or mitigation, most of them with limited success:
U.S. Pat. No. 5,785,779 issued July, 1998 to McGee et al. describes a Kevlar(copyright) tire liner, similar to a toughie. The McGee device is not an inner tube, nor is the insert inflatable, it is a strip of material that rests between the inner tube and the tire. Thus, McGee et al. do not teach the present invention as claimed.
U.S. Pat. No. 4,945,965 issued on August, 1990 to Kim, describes a tire having deflatable safety balloons between the tread and the main compressible area of the tire (the inner tube). The safety balloons, when punctured, deflate to allow contiguous balloons to occupy the vacuum resulting from the deflated balloon. Kim does not teach the present invention as claimed.
U.S. Pat. No. 3,831,653 issued on August, 1974 to Moore, describes a vehicle tire casing in combination with a flexible lead tube. However, lead and the other specified metals add excessive weight to the inner tube, they tend to conduct heat, fracture, and are subject to oxidization. Moore does not teach the present invention as claimed.
U.S. Pat. No. 4,263,074 issued on April, 1981 to Price, describes a trough-shaped tire liner. U.S. Pat. No. 4,347,884 issued on September, 1982 to Price, D. R. describes another tire liner. Neither ""074 nor ""884 patent teaches the present invention as claimed.
U.S. Pat. No. 5,679,184 issued on October, 1997 to Hosking, describes a resiliently deformable polyurethane ring between the rim and the inner tube, designed for preventing xe2x80x9cpinch punctures,xe2x80x9d also known as xe2x80x9csnake bites.xe2x80x9d Hosking does not teach the present invention as claimed.
U.S. Pat. No. 5,685,925 issued on November, 1997 to Riquier et al. describes a tire device, principally for military use, comprising a toroidal cushion in which airtight channels extend circumferentially through the cushion. Riquier does not teach the present invention as claimed.
U.S. Pat. No. 5,795,414 issued on August, 1998 to Chih, describes a puncture resistant tire assembly marked by an inner tube segment having finger-like deflector structures cooperating with a tire liner having ridge-like separator structures. Chih does not teach the present invention as claimed.
British Patent No. 439,322 having an application date of September, 1934 describes an impermeable coating, such as tanned gelatin, for rubber inner tubes. British Pat. No. 439,322 does not teach the present invention as claimed.
British Patent No. 458,167 having an application date of March, 1935 describes an inner tube having thickened portions that provide the inner tube with better self-sealing properties. British Pat. No. 458,167 does not teach the present invention as claimed.
British Patent No. 342,675 having an application date of October, 1929 describes a durable and efficient xe2x80x9cbuilt-upxe2x80x9d inner tube. The rubber inner tube maintains layers of carbon black sheet rubber, and tough tread rubber, disposed on the surface that faces the tire. British Pat. No. 342,675 does not teach the present invention as claimed.
None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed. Thus a puncture proof inner tube solving the aforementioned problems is desired.
The present invention is an improved pneumatic chamber formed from a semi-rigid rubber layer, encased by a puncture proof plurality of layers. The composition can be used as inner tubing for cars, bikes, motorcycles, planes, and any kind of vehicle having pneumatic inner tubes. It can also be formed into a puncture proof rubber raft. The preferred device is constructed from a toroid-shaped, thick-walled, semi-rigid, air-tight core chamber. A plurality of toroid-shaped layers of armored material, such as that under the trade name Kevlar(copyright), Spectraflex(copyright), or similar flexible puncture-proof webbing, is bonded to the exterior wall of the core chamber.
Since the inner tube of the present invention is semi-rigid and has a 100% armored exterior surface, flats that would otherwise be caused by pinching of the tube are avoided; the tube is resistant to flats caused by blunt forces, e.g. a curb; and it is generally puncture proof. It is great for off-road riding on any kind of terrain. Once the inner tube is in place, it is good for years of uninterrupted use and, at the very least, for the life of the tire. The composition can also be used to make puncture proof rubber rafts.
Accordingly, it is a principal object of the invention to provide an armored inner tube that can prevent punctures from occurring at any location on the tube.
It is another object of the invention to provide a thick, semi-rigid inner tube that is resistant to pinch-type or xe2x80x9csnake bitexe2x80x9d punctures, and will not blister, i.e., will remain intact even if the tire itself splits open.
It is a further object of the invention to provide an armored rubber composition that when used as a water craft, or as an inner tube, enables uninterrupted use throughout the life of the craft or tire.
It is an object of the invention to provide improved elements and arrangements thereof for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.